This invention relates to a technique for treating stainless steel to reduce corrosion, and more particularly to stainless steels which contain both a martensitic and metastable austenitic phase, such as 17-4 PH (AISI 630 modified) or AISI type 301.
Before the development of this technique, chlorine induced corrosion assisted cracking was a very significant problem. In steam turbines, for example, chlorine ion environments had cause a large number of blade cracking incidents resulting in significant turbine downtime.